Synergistically optimizing charge and phonon transport properties in n-type PbTe via introducing ternary compound AgSb(Se, Te)2

PbTe-based thermoelectric materials are considered to be a medium-temperature thermoelectric candidates and the high-performance n -type PbTe is urgently to be developed to match its p -type counterpart on account of practical application. Herein, we firstly optimized the carrier density of n -type PbTe through Sb doping, and obtained a maximum ZT value of ∼1.0. Then, based on the optimized carrier density, we introduced ternary compounds AgSb(Se, Te) 2 to suppress the lattice thermal conductivity . Minimum lattice thermal conductivity of n -type PbTe was reduced as low as ∼0.53 W m −1 K −1 and ∼0.62 Wm −1 K −1 through introducing AgSbSe 2 and AgSbTe 2 , respectively. Combining the maintained electrical properties with suppressed thermal conductivity , maximum ZT values ∼1.2 and ∼1.3 were obtained in PbTe+2%AgSbSe 2 and PbTe+2%AgSbTe 2 , respectively. This work provides an effective strategy of synergistically balancing charge and phonon transports in n -type PbTe with ternary AgSb(Se, Te) 2 compounds.